Powering a Garmin Edge 520

Garmin do a powerpack that fits under the outfront mount

It's pricey enough, at just over a hundred quid.

I'm not sure if you could plug a powerbank into the charge port, and keep the bank itself in a toptube bag or similar.

The other option is to have the battery replaced. The are a number of websites detailing how you might do that

*edit* actually, scrap the link above looks like it's only for the 1030

I have a 520 plus* and use a Gomadic portable charger for longer rides. It takes 4xAA batteries. There are two ways of doing it - either boost the battery on tea stops or continually charge it on the move. To charge on the move you'll need some sort of bar bag to hold the charger. You'll probable also need an 'out front' Garmin mount to make the charging easier. The disadvantage of charging on the move is that it can be awkward on wet days. The fact that it uses AA batteries means you can stop at any shop to replace them should they run flat. As has been said, if using any normal power pack, you need to make sure the cable isn't a data one or the Garmin will reset.

*I've subsequently bought a 530 which has a much longer battery life so now only use the 520 for short rides, commutes, walks etc.

https://www.amazon.co.uk/Gomadic-Portable-Battery-designed-Garmin/dp/B00BDBXGAQ

I think the 520 was quite a short battery life, as per the OP, depending on sensors, navigation etc . on the reviews I read when I was buying the computer before my current. It was the reason I went for a Bolt over it it.

I got a 530 for Christmas, which seems to be matching the Bolt battery wise.

If your stem is reasonably long, you may be able to charge on the move without an out front mount.

People can be awfully free with other people's money 😁

There's a big difference between buying an Anker power bank for 50 quid, and a new head unit for 260

Or second hand Bolt, coming soon to Cycling Adverts!

My 520's battery had become unmanageable for anything over 40km. Before it got that bad, I used a cheapo Pennys power bank. When the battery on the 520 went below 10% I removed it from the mount, connected it to the power bank and stuffed both into a jersey pocket. I found that as battery life deteriorated, charge time shortened accordingly so it would charge to 100% quite quickly. I often considered using a couple of heavy duty elastic bands to strap the power bank under the stem but a new Wahoo was a better option.

I did a sportive a few years ago and the "Goodie" bag included a USB power pack about the size of a Bic Lighter. Since then i carry it with me on long days out and use it to recharge my Garmin 1000..works a treat! (i just tie the battery pack to the stem and connect it to the Garmin with a short USB cable)